“A timely warning” and a “call to conscience” is how former Irish president Mary Robinson has described a book just published by Vice Admiral Mark Mellett.
Entitled Blue Heart: War, Climate and the Battle for the Ocean That Keeps Us Alive, the book by the retired Defence Forces chief of staff offers what one critic describes as a “passionate, thoughtful and powerful argument” for ocean health, drawing on a lifetime in the Naval Service.
Former Taoiseach Enda Kenny marked its publication at a function in Dublin earlier this week.
In his book, Mellett argues that the defining crises of the 21st century—climate change, energy insecurity, geopolitical instability, food vulnerability, and the erosion of democratic resilience—are converging at sea.
Drawing on a lifetime in naval command and international security, Mellett examines how the ocean has quietly sustained the modern world: regulating climate, absorbing carbon, carrying global trade, supporting food systems and enabling the undersea digital networks on which economies now depend.
Early immersion — Mark Mellett as a young Naval Service diver, beginning a maritime career that would span almost four decades and later inform his book Blue Heart
Yet as he points out, this vast living system is under mounting pressure from warming waters, biodiversity collapse, overexploitation and intensifying strategic competition.
From the North Atlantic to the deep waters west of Ireland, from vulnerable undersea cables to contested energy infrastructure, Blue Heart “reveals an ocean becoming both more fragile and more geopolitically significant”, the publishers state.
“Mellett explores the rise of hybrid maritime conflict, the risks posed by failing governance systems, and the profound implications of climate disruption for migration, sovereignty and global security.”
Mellett, from Co. Mayo, has over 39 years’ service as an officer in the Defence Forces and was the first naval officer in the State's history to serve as Chief of Defence, having previously served as Deputy Chief of Defence and Chief of Navy.
He has extensive experience at home and abroad, including in Afghanistan and Lebanon. He holds a PhD in Political Science from the University of Galway.
